Little Long Lake

Little Long Lake sits at the top of the Minnesota PCA grading rubric with an A, a mark reached by the cleanest lakes in Minnesota. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

The lake's low TSI puts it in oligotrophic territory — the cleanest of the four trophic classes, but also the most vulnerable to nutrient-driven shifts. The lake bottoms out at 45 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 322 acres, Little Long Lake fits the Minnesota median for monitored lakes, with 6.5 miles of shoreline. Within St. Louis County's 187 graded waters, Little Long Lake sits at rank 10, near the top of the local distribution.

No invasive species are currently listed at Little Long Lake — the lake remains off the Minnesota infested-waters roster. Walleye are documented at Little Long Lake, one of 11 fish species on record for the lake. A documented public access point at Little Long Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. Ice-out has been recorded 13 times at Little Long Lake, with a median around Apr 28. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.